java update Jpanel component_问答_开发者_运维开发者技术经验分享

开发者 https://www.devze.com 2023-02-11 07:26 出处：网络

I am using a Custome jPanel in my Gui Builder JFram Class A, the problem i am facing is to update the components (Lable) in my JPanel when I click button in JFrame.here is the button in Gui Builder JFrame ClassA: it changes the color of Jpl and also remove all the labels but not update the new labels.

private void btnShowActionPerformed(java.awt.event.ActionEvent evt) {
    // TODO add your handling code here:

            Random randomGenerator = new Random();
            for (int idx = 1; idx <= 10; ++idx) {
                q = randomGenerator.nextInt(100);
            }
            jpl1.removeAll();
            new Jpl().printMe(ClassA.q);
            jpl1.revalidate();
            jpl1.setBackground(Color.BLUE);
            jpl1.repaint();
}

here is Jpl class that is used as a custome component in GuiBuilder JFrame Class A.

public class Jpl extends JPanel {

public Jpl() {
    printMe(ClassA.q);
}


public void printMe(int q) {

    for (int i = 0; i <q; i++) {
        System.out.println(i+"rinting lable");
        String htmlLabel = "<html><font color=\"#A01070\">" + i + " New Lable </font></html>";
        JLabel lbl = new JLabel(htmlLabel);
        setLayout(new GridLayout(0, 1));
        add(lbl, Jpl.RIGHT_ALIGNMENT);
        lbl.setForeground(Color.BLUE);
        Border border = BorderFactory.createLineBorder(Color.lightGray)开发者_运维百科;
        lbl.setBorder(border);
        lbl.add(new JSeparator(SwingConstants.HORIZONTAL));

        lbl.addMouseListener(new MouseAdapter() {

            @Override
            public void mousePressed(MouseEvent e) {
                JLabel label = (JLabel) e.getSource();
                JOptionPane.showMessageDialog(null, "You Slected");
                System.out.println(label.getText() + "NO AKKA is Selected");
            }
        });
    }

}

You are calling printMe() on a new instance of Jpl, try that:

private void btnShowActionPerformed(java.awt.event.ActionEvent evt) {
    // TODO add your handling code here:

            Random randomGenerator = new Random();
            for (int idx = 1; idx <= 10; ++idx) {
                q = randomGenerator.nextInt(100);
            }
            jpl1.removeAll();
            jpl1.printMe(ClassA.q); // HERE - REMOVED new and using jpl1 instance
            jpl1.setBackground(Color.BLUE);
            jpl1.revalidate();
            jpl1.repaint();
}

In don't understand why you loop 10 times for your random number. Only the last result will be kept, maybe a you wanted to use q += randomGenerator.nextInt(100);. Also, ClassA.q should be replaced by q if it's the same variable.